1. Field of the Invention
The present invention relates to an electrophotographic image forming apparatus and a cartridge support member in which a process cartridge is detachably mounted to an apparatus main body.
2. Description of the Related Art
As used here, an electrophotographic image forming apparatus forms an image on a recording medium by using an electrophotographic image forming method. Examples of the electrophotographic image forming apparatus include electrophotographic copiers, electrophotographic printers (e.g., laser beam printers, LED printers, etc.), facsimile machines, word processors, and so on. Here, note that the recording medium is an object on which an image is formed by using the above-mentioned electrophotographic image forming method. The above-mentioned recording medium is, for example, paper, a plastic sheet, an OHP sheet, etc.
In addition, the process cartridge has a process unit, which includes at least one of a charging means, a developing means and a cleaning means, and an electrophotographic photosensitive drum formed into a cartridge in an integrated manner, so that it is adapted to be detachably mounted to a main body of the electrophotographic image forming apparatus. Accordingly, the process cartridge includes one in which a development means as a process unit and an electrophotographic photosensitive drum are formed into a cartridge in an integrated manner so that it is detachably mounted to the main body of the electrophotographic image forming apparatus. Further, the process cartridge includes another one in which a charging means, a development means or a cleaning means as a process unit and an electrophotographic photosensitive drum are formed into a cartridge in an integrated manner so that it is detachably mounted to the main body of the electrophotographic image forming apparatus. Here, since the above-mentioned process cartridge can be easily attached to and detached from the apparatus main body by a user himself or herself, it is possible to perform the maintenance of the apparatus main body in an easy manner. In this regard, note that the above-mentioned process unit acts on the electrophotographic photosensitive drum.
Here, it is generally considered that the temperature inside the cartridge is controlled not to become too high so as to prevent deterioration in quality of the process cartridge (hereinafter referred to simply as a cartridge). Specifically, in case where a developer (toner) is contained in the cartridge, it is necessary to avoid the temperature of the developer from exceeding its melting point for the purpose of preventing the melting and/or fusion of the developer. Also, in the case where there is a member composed of a rubber material in a part provided within the cartridge, it is necessary to prevent the part from softening due to a rise in the temperature thereof. Here, note that as a representative example of the member composed of a rubber material, there is exemplified a cleaning blade that removes a residual toner on a surface of an electrophotographic photosensitive member.
Accordingly, in the past, there has been known a technique in which a ventilation channel for sending outside air into the apparatus main body or a fan for blowing air into the apparatus main body in a forced manner is arranged in the apparatus main body in order to cool the cartridge. However, in general, such a cartridge might sometimes be arranged in a position where air ventilation is relatively poor in the apparatus main body for the reason that a variety of kinds of component parts have to be arranged in the surroundings of the cartridge.
Accordingly, a special duct sometimes has to be arranged for guiding outside air from a frame side of the apparatus main body up to the position of the cartridge. However, a plurality of parts generally exist in the vicinity of the cartridge, as stated above, and it might be difficult to ensure a route for guiding the outside air. Therefore, it has sometimes been necessary to ensure a space for arrangement of such a special duct, or to use a duct of a complex shape or geometric structure.
Thus, in the past, there has been used the special duct or the like, for blowing outside air into the cartridge, so the number of parts required is increased, giving rise to an impediment to making the apparatus compact and small in size. In addition, the need for the special duct or the like has resulted in the cause of a cost increase in the apparatus.
Here, note that as a relevant technique, there is one disclosed in Japanese patent application laid-open No. 2005-37704.